# SDR BB07074

- Type: Service difficulty report (as reported; unverified)
- Difficulty date: September 17, 2007
- Submitted: September 20, 2007
- Operation: Air carrier
- Aircraft: N201UU
- Make and model: Boeing 757-2B7
- Registry model: [Boeing 757-2B7](https://openairdocs.org/model/boeing-757-2b7) (OpenAirDocs)
- Aircraft serial: 27810
- Aircraft time: 41,789 hours, 16,858 cycles
- System (JASC): [2120 · Air Distribution System](https://openairdocs.org/jasc/2120)
- Part: Diffuser
- Condition: Cracked
- Location: Cockpit
- Stage of operation: CR
- How discovered: O
- Nature of condition: O
- Precautionary procedure: A
- FAA source: FAA Service Difficulty Reporting System (https://sdrs.faa.gov/)
- Page: https://openairdocs.org/sdr/BB07074

## Discrepancy

FLIGHT 731, LGW-PHL:  DURING FLIGHT, THE CAPTAIN REPORTED DIFFICULTY HEARING RADIO TRANSMISSIONS DUE TO EXCESSIVE AIR NOISE IN THE COCKPIT.  DIVERTED TO SNN.  MAINTENANCE PLACED THE LEFT PACK ON MEL.  SUBSEQUENT TROUBLESHOOTING DETERMINED THAT THE F/O'S WINDSHIELD AIR DIFFUSER WAS CRACKED AND A LOUD HUM WOULD DEVELOPE WITH THE PACK ON.  REPAIRED DIFFUSER.  NO FURTHER FAULTS.

---
OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.